Analog Devices Linear Technology DC2564A User manual

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DEMO MANUAL DC2564A
DESCRIPTION
LT8606
42V, 0.35A Micropower Synchronous
Step-Down Regulator
Demonstration Circuit 2564A is a 42V, 0.35A micropower
synchronous step-down regulator featuring the LT
®
8606.
The demo board is designed for 5V output from a 5.5V
to 42V input. The wide input range allows a variety of
input sources, such as automotive batteries and indus-
trial supplies. The LT8606 is a compact, high efficiency,
high speed synchronous monolithic step-down switch-
ing regulator that consumes less than 3μA of quiescent
current when output is regulated at 5V. Top and bottom
power switches, compensation components and other
necessary circuits are inside of the LT8606 to minimize
external components and simplify design.
The SYNC pin on the demo board is grounded by default
for low ripple Burst Mode
®
operation. Move JP1 to PULSE
SKIPPING position can change the operation mode to
pulse-skipping operation. Once JP1 is on SPREAD SPEC-
TRUM position, VCC is applied to the SYNC pin for low
EMI spread spectrum operation. To synchronous to an
external clock, move JP1 to SYNC and apply the external
L, LT, LTC, LTM, Linear Technology, the Linear logo and Burst Mode are registered trademarks
of Analog Devices, Inc. All other trademarks are the property of their respective owners.
PERFORMANCE SUMMARY
clock to the SYNC turret. Figure 1 shows the efficiency
of the circuit.
The demo board has an EMI filter installed. The radiated
EMI performances of the board (with EMI filter) are shown
in Figures 2 and 3. The red/green lines in Figures 2 and
3 are CISPR25 Class 5 peak/average limit. To use the
EMI filter, the input should be tied to VEMI, not VIN. An
inductor L2, which is a 0Ω jumper on the board by default
now, can be added in the EMI filter to further reduce the
conducted emission.
The LT8606 data sheet gives a complete description of
the part, operation and application information. The data
sheet must be read in conjunction with this demo manual
for DC2564A.
Design files for this circuit board are available at
http://www.linear.com/demo/DC2564A
Specifications are at TA= 25°C
SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
VIN Input Voltage Range 5.5 42 V
VOUT Output Voltage 4.8 5 5.2 V
IOUT Maximum Output Current 0.35 A
fSW Switching Frequency 1.85 2 2.15 MHz
EFE Efficiency at DC VIN = 12V, IOUT = 0.35A 92.1 %

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DEMO MANUAL DC2564A
QUICK START PROCEDURE
DC2564A is easy to set up to evaluate the performance
of the LT8606. Refer to Figure 4 for proper measurement
equipment setup and follow the procedure below:
NOTE:When measuring the input or output voltage ripple,
care must be taken to avoid a long ground lead on the
oscilloscope probe. See Figure 5 for the proper scope
technique.
1. Set an input power supply that is capable of 42V/0.35A.
Then turn off the supply.
2. Withpoweroff,connectthesupplytotheinputterminals
VIN and GND.
3. Turn on the power at the input.
NOTE: Make sure that the input voltage never exceeds
42V.
4. Check for the proper output voltage of 5V. Turn off the
power at the input.
5. Once the proper output voltage is established, connect
a variable load capable of sinking 0.35A at 5V to the
output terminals VOUT and GND. Set the current for 0A.
a. Ifefficiency measurements are desired, an ammeter
can be put in series with the output load in order
to measure the DC2564A’s output current.
b. A voltmeter can be placed across the output ter-
minals in order to get an accurate output voltage
measurement.
6. Turn on the power at the input.
NOTE: If there is no output, temporarily disconnect the
load to make sure that the load is not set too high.
7. Once the proper output voltage is established again,
adjust the load and/or input within the operating range
and observe the output voltage regulation, ripple volt-
age, efficiency and other desired parameters.
8. An external clock can be added to the SYNC terminal
when SYNC function is used (JP1 on the SYNC posi-
tion). Please ensure that the chosen RT sets the LT8606
switching frequency to equal or below the lowest SYNC
frequency. See the data sheet section, Synchronization.
Figure 1. Efficiency vs Load Current at 2MHz Switching Frequency
IOUT (A)
0
EFFICIENCY (%)
100
55
95
85
75
65
90
80
70
60
50 0.10 0.300.20
dn2564 F01
0.35
0.05 0.250.15
12VIN
24VIN

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DEMO MANUAL DC2564A
QUICK START PROCEDURE
Figure 2. LT8606 Demo Circuit EMI Performance in CISPR25 Radiated Emission Test, Antenna Polarization:
Vertical, Peak Detector (VIN = 14V, VOUT = 5V, IOUT = 0.35A, 2MHz Switching Frequency)

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DEMO MANUAL DC2564A
QUICK START PROCEDURE
Figure 3. LT8606 Demo Circuit EMI Performance in CISPR25 Radiated Emission Test, Antenna Polarization:
Vertical, Average Detector (VIN = 14V, VOUT = 5V, IOUT = 0.35A, 2MHz Switching Frequency)

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DEMO MANUAL DC2564A
QUICK START PROCEDURE
Figure 4. Proper Measurement Equipment Setup
Figure 5. Measuring Output Ripple
V
OUT
GND

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DEMO MANUAL DC2564A
PARTS LIST
ITEM QTY REFERENCE PART DESCRIPTION MANUFACTURER/PART NUMBER
Required Circuit Components
1 1 C2 CAP., X7R, 1µF, 50V, 10% 0805 MURATA, GRM21BR71H105KA12L
2 1 C4 CAP., X7R, 0.22µF, 16V, 10%, 0603 MURATA, GRM188R71C224KA01D
3 1 C5 CAP., C0G, 10pF, 25V, 5%, 0603 AVX, 06033A100JAT2A
4 1 C6 CAP., X7R, 10µF, 10V, 10%, 0805 MURATA, GRM21BR71A106KE51K
5 1 C7 CAP., X7R, 1µF, 25V, 10%, 0603 MURATA, GRM188R71E105KA12D
6 1 C8 CAP., X7R, 0.01µF, 16V, 10%, 0603 MURATA, GRM188R71C103KA01D
7 1 L1 IND., 4.7µH WURTH ELECTRONICS, 74438336047
8 1 R2 RES., CHIP, 18.2k, 1/10W, 1%, 0603 VISHAY, CRCW060318K2FKEA
9 1 R3 RES., CHIP, 49.9k, 1/10W, 1%, 0603 VISHAY, CRCW060349K9FKEA
10 2 R1, R4 RES., CHIP, 1M, 1/10W, 1%, 0603 VISHAY, CRCW06031M00FKEA
11 1 R5 RES., CHIP, 187k, 1/10W, 1%, 0603 VISHAY, CRCW0603187KFKEA
12 1 U1 IC, REGULATOR, MSE10 LINEAR TECH., LT8606EMSE#PBF
Additional Demo Board Circuit Components
1 1 C1 CAP., ALUM 22µF 63V SUN ELECT, 63CE22BS
2 3 C3, C10, C11 CAP., X7R, 1µF, 50V, 10% 0805 MURATA, GRM21BR71H105KA12L
3 1 C9 CAP., X7R, 4.7µF, 16V, 10%, 0805 MURATA, GRM21BR71C475K73L
4 2 C12, C13 CAP., X7R, 0.1µF, 50V, 10%, 0603 MURATA, GRM188R71H104KA93D
5 1 FB1 FERRITE BEAD 0805 TDK, MPZ2012S331AT000
6 1 L2 RES., CHIP, 0Ω, 3/4W, 2010 VISHAY, CRCW20100000Z0EF
7 0 R6 (OPT.) RES., 0603
Hardware: For Demo Board Only
1 9 E1 - E9 TESTPOINT, TURRET, 0.094" MILL-MAX, 2501-2-00-80-00-00-07-0
2 1 E10 (OPT.) TESTPOINT, TURRET, 0.094"
3 1 JP1 DOUBLE ROW HEADER 2 x 4 0.079" WURTH ELECTRONICS, 62000821121
4 1 XJP1 SHUNT, 0.079" CENTER WURTH ELECTRONICS, 60800213421
5 4 MH1-MH4 STAND-OFF, NYLON 0.50" TALL WURTH ELECTRONICS, 702935000

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DEMO MANUAL DC2564A
Information furnished by Linear Technology Corporation is believed to be accurate and reliable.
However, no responsibility is assumed for its use. Linear Technology Corporation makes no representa-
tion that the interconnection of its circuits as described herein will not infringe on existing patent rights.
SCHEMATIC DIAGRAM
5
5
4
4
3
3
2
2
1
1
DD C C
B B
A A
ALL CAPACITORS ARE 0603.
NOTES: UNLESS OTHERWISE SPECIFIED
1. ALL RESISTORS ARE 0603.
SUNCON 63CE22BS
(2MHz)
SYNC SPREAD SPECTRUM PULSE SKIPPING BURST
VOUT
VCC
VCC
E7
TR/SS
C12 0.1µF 50V
R6 (Opt)
C5
10pF
R5 187k
C10 1µF 50V 0805
C6
10µF 10V
0805
JP1
1 2
3 5 7
4 6
8
R1 1.00M
R4
1.00M
E6
EN/UV
U1 LT8606EMSE
VIN
9
EN/UV
10
SYNC
5
VCC
3
TR/SS
7
RT
4
FB 6
PG 8
SW 2
BST 1
GND
11
+
C1 22µF 63V
C13 0.1µF 50V
C7
1µF
C3 1µF 50V 0805
E4
GND
E5
SYNC
C11 1µF
50V
0805
L1
4.7µH
74438336047
E10
VIN
5.5V - 42V
R2
18.2k
FB1
MPZ2012S331AT000
E2
GND
C4
0.22µF
L2
0 2010
E8 PG
E3
VOUT
5V / 0.35A
C8
0.01µF
R3 49.9k
E9
GND
C2 1µF 50V 0805
E1
VEMI
5.5V - 42V
C9 4.7µF 16V 0805

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DEMO MANUAL DC2564A
 LINEAR TECHNOLOGY CORPORATION 2017
LT 0417 • PRINTED IN USA
DEMONSTRATION BOARD IMPORTANT NOTICE
Linear Technology Corporation (LTC) provides the enclosed product(s) under the following AS IS conditions:
This demonstration board (DEMO BOARD) kit being sold or provided by Linear Technology is intended for use for ENGINEERING DEVELOPMENT
OR EVALUATION PURPOSES ONLY and is not provided by LTC for commercial use. As such, the DEMO BOARD herein may not be complete
in terms of required design-, marketing-, and/or manufacturing-related protective considerations, including but not limited to product safety
measures typically found in finished commercial goods. As a prototype, this product does not fall within the scope of the European Union
directive on electromagnetic compatibility and therefore may or may not meet the technical requirements of the directive, or other regulations.
If this evaluation kit does not meet the specifications recited in the DEMO BOARD manual the kit may be returned within 30 days from the date
of delivery for a full refund. THE FOREGOING WARRANTY IS THE EXCLUSIVE WARRANTY MADE BY THE SELLER TO BUYER AND IS IN LIEU
OF ALL OTHER WARRANTIES, EXPRESSED, IMPLIED, OR STATUTORY, INCLUDING ANY WARRANTY OF MERCHANTABILITY OR FITNESS
FOR ANY PARTICULAR PURPOSE. EXCEPT TO THE EXTENT OF THIS INDEMNITY, NEITHER PARTY SHALL BE LIABLE TO THE OTHER FOR
ANY INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES.
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arising from the handling or use of the goods. Due to the open construction of the product, it is the user’s responsibility to take any and all
appropriate precautions with regard to electrostatic discharge. Also be aware that the products herein may not be regulatory compliant or
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observe good laboratory practice standards. Common sense is encouraged.
This notice contains important safety information about temperatures and voltages. For further safety concerns, please contact a LTC application
engineer.
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